Process for the production of animal feed and ethanol and novel animal feed

ABSTRACT

A method for the production of ethanol and a modified animal feed is provided. The method replaces the starch in known corn-based animal feed with biomass fiber treated to make it more digestible by animals. The process includes wherein the pericarp and germ are removed from the corn kernel and processed for by-products. The starch and protein are also removed and separated. The starch is then fermented and distilled to ethanol and stillage. The bioavailable modified animal feed comprises the pericarp and germ removed from corn kernels and optionally by-products of the pericarp and germ processing, and lignocellulosic materials. The modified animal feed may optionally include energy materials such as animal and vegetable fats, vegetable soapstocks, or glycerin, and combinations thereof.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a nonprovisional of and claims the benefit ofpriority to U.S. Provisional Patent Application Ser. No. 60/672,779,filed on Apr. 19, 2005, entitled “Process For The Production Of AnimalFeed And Ethanol And Novel Animal Feed”, having the same namedapplicants as inventors, namely, Charles Abbas, Thomas P. Binder, KyleE. Beery, Michael J. Cecava, Perry H. Doane, David P. Holzgraefe, andLeif P. Solheim. The entire contents of U.S. Provisional PatentApplication Ser. No. 60/672,779 are incorporated by reference into thisnonprovisional utility patent application.

STATEMENT OF FEDERALLY SPONSORED RESEARCH

The U.S. Government has a paid-up license in this invention and theright in limited circumstances to require the patent owner to licenseothers on reasonable terms as provided for by the terms of Award NumberNRCS 68-3A75-3-140 awarded by U.S.D.A.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to methods of producing a novel bioavailablemodified animal feed and expanding ethanol production, and a novelbioavailable modified animal, preferably cattle, feed.

2. Description of the Background Art

Within the new Energy Bill is a Renewable Fuels Standard requiringrenewable fuel production of 7.5 billion gallons by 2012. This increasefrom the current level of 3.8 billion gallons of ethanol will almostcertainly take place by increasing the amount of ethanol produced fromcorn, specifically from dry-milling of corn. Dry milling of corn is themost cost effective way to increase the production of ethanol, andproduces the fewest and lowest volume of by-products.

Over 11 billion bushels of corn were harvested in 2005; however, onlyapproximately 2.6 billion bushels were processed by wet or dry milling,with only approximately 1.4 billion bushels processed for ethanolproduction. The remaining 8.4 billion bushels of corn are utilizedmainly as animal feed, with over 2 billion bushels as cattle or dairyfeed. Corn is fed to provide an inexpensive energy and protein source tofeeder and dairy cattle; however, the starch in corn is readilymetabolized by the rumen microorganisms. These organisms ferment thestarch to organic acids, which at high concentrations can lead toacidosis in the cattle. Based on research completed by ADM AllianceNutrition, approximately 550 million bushels could be diverted from useas cattle or dairy feed to ethanol, if a >60% digestible cornreplacement could be produced. If the 550 million bushels of corn wereto be diverted to produce ethanol by dry milling, an additional 1.5billion gallons of ethanol could be produced. Based on a currentproduction of 3.8 billion gallons of ethanol in 2006, this wouldincrease the total ethanol production by 40% without increasing cornacreage planted.

The present invention provides for several cost effective ways thatfacilitate the expansion of ethanol dry mill corn refineries whilemaintaining adequate cattle feed supplies to the market. This inventionalso outlines new approaches to processing corn in dry mills. Part ofthe plan to maintain cattle feed supplies includes treating variousbiomass fiber sources to increase the digestibility for cattle, toprovide a corn replacement pellet.

By diverting this corn from cattle feed to ethanol production, twoissues will arise. The first issue is the loss of energy from starch forcattle feed, and the second is the additional production of corn drymilling byproducts, which will greatly over-saturate the animal feedmarket. Both of these issues can be addressed by upgrading the drymilling by-products to an enhanced cattle feed to replace the energyfrom starch.

To replace the estimated 550 million bushels of corn which could bediverted annually from dairy and beef cattle feed, an equivalent amountof bio-available feed would need to be substituted for the corn. The 550million bushels of corn are equivalent to 26.4 billion pounds total,comprising approximately 19.6 billion pounds of starch, and 3.09 billionpounds of lignocellulosics. By the current dry milling process, 550million bushels of corn would yield 9.2 billion pounds of distillersdried grains (DDG) and distillers dried grains with solubles (DDGS),which are the major by-products of the dry-milling process. Therefore,an additional 17.2 billion pounds of similarly bio-available feed wouldneed to be made up by currently available lignocellulosics, such assoybeans hulls, corn stover, or wheat straw. The energy content of thefeedstocks would also need to be determined to ensure an equivalentamount of feed energy value for the new bio-available cattle feed.

Cattle are able to utilize the protein from DDG and DDGS in their diet.The cellulose and hemicellulose are broken down enzymatically in therumen of the animal as a source of mono- and di-saccharides. The DDGSalso contain vitamins and minerals that are beneficial to animals suchas cattle.

It is therefore an object of this invention to enable the expansion ofethanol production by corn dry-milling while ensuring adequate feedsupply to the cattle market by supplementing the DDG and DDGS producedas a by-product of the dry-milling process with other agriculturalprocessing by-products and pretreated agricultural residues.

The known in the art current method of corn dry-milling is composed ofan initial cleaning step by screening (sieving) to remove small brokenkernels and impurities and aspiration to remove light impurities for thecorn followed by a grinding step utilizing a hammermill or a rollermill. The ground corn is generally heated to 125-150° C. for 10 secondsthrough a jet cooker at a pressure of about 5.1 bar and then held at 95°C. at ambient pressure for 10 minutes, with 2 times the mass of wateradded to the ground corn prior to jet cooking, and a high-temperature(from about 80° C. to about 99° C.) α-amylase enzyme (0.01% wt/wtaddition) to liquefy the starch to oligosaccharides. The liquefiedstarch is then cooled to 30° C. and saccharified to glucose by utilizinga glucoamylase (0.01% wt/wt addition) enzyme while simultaneouslyfermented in a fermentation vessel with Saccharomyces cerevisiae toethanol at ambient pressure and pH 4-5 for 48 hours. The insolublepericarp, protein, tip cap, and germ are not separated during theprocessing and fermentation of the starch. The glucose is fermentedprimarily by yeast to ethanol with carbon dioxide as a co-product. Thetheoretical production is 0.51 wt % ethanol and 0.49 wt % carbondioxide. The glucose concentration is between 200-350 grams per liter inthe fermentation broth, which, when fermented, gives a final ethanolconcentration of 13-23% on a volume ethanol/volume of fermentation brothbasis. The ethanol is distilled at temperatures between 80 and 100° C.and 1.1 bar from the fermentation broth to a final ethanol concentrationof 95% and then further dehydrated to 100% by passing the ethanol/watervapors through an adsorption system at 82° C. and at 1.1 bar. The waterand solids in the fermentation broth is called stillage and leaves thebottom of the distillation column at ambient pressure and 80° C. Thesolids remaining in the fermentation broth (pericarp, protein, germ, andtip cap) are separated from the liquid utilizing a centrifuge andoptionally dried through a gas-fired rotary drum dryer and agglomeratedthrough a pellet mill or extruder to create distiller's dried grains,which are sold primarily as an animal feed.

SUMMARY OF THE INVENTION

The object of the invention will be accomplished by greater utilizationof pretreated lignocellulosics, which are derived from current crops andexisting agricultural processing operations, as animal feed. Thisinvention creates a bio-available cattle feed by mixing pretreatedagricultural processing by-products and pretreated agriculturalresidues.

Upgrading the DDG and DDGS can be achieved by mixing these by-productsof the dry-milling process with thermochemically, chemicallyenzymatically and/or physically pretreated corn stover, wheat straw,corn meal germ, soybean hulls, rice straw, oat hulls, solid edible beanbyproducts, cottonseed hulls, barley hulls, other forage crop fibers, orother cellulosic biomass.

The composition of DDG and DDGS and other agricultural processingby-products and pretreated agricultural residues are found in Table 1below.

TABLE 1 Approximate Feedstock Compositions Feedstock CelluloseHemicellulose Starch Fat Ash Protein Lignin Pectin and Gums Corn  2.0% 7.6% 76.0% 5.7% 1.6% 11.4% 1.0% Corn Fiber Hulls 16.0% 40.0% 18.0% 3.0%3.0% 11.0% 4.0% DDG/DDGS 22-26%   24-28%   8-12%   2.50%  26-29%   4.0%Corn Gluten Feed 25.1% 23.0% 3.3% 8.2% 23.9% Corn Germ Meal   12%   25%  12%   3%   3%   22%   2% Corn Stover 38.0% 25.0% 3.3% 6.1%  4.0%17.5%  Soybean  2.0%  5.0% 18.8%  5.5% 42.8% 7-15% Soybean Hulls 46.0%18.0% 2.5% 5.0% 12.0% 2.0% Wheat  8.0%  4.0% 70.0% 2.2% 1.6% 12.3% 2.0%Wheat Straw 35.0% 24.0% 6.0%  4.0% 25.0%   Switchgrass 33.5% 26.5% 6.4% 5.3% 18.1%   Brown rice  1.0%  2.0% 74.4% 2.6% 1.6%  8.5% Rice Hulls30.0% 20.0% 0.8% 16.3%   3.2% 21.4%   Oat 11.0% 15.0% 68.2% 5.4% 3.4%13.3% 2.7% Oat Hulls 30.0% 34.0% 1.6% 6.1%  3.6% 13.2%   Cocoa Shells13.7%  7.1% 8.3% 15.3%  3.4%   8.0% Cottonseed Hulls 59.0% 1.7% 2.8%24.0%  Barley  5.0%   13% 78.8% 3.9% 2.2% 12.8% 2.0%

A pretreatment process is used to enhance the digestibility of thecellulosic materials by the cattle. A thermochemical treatment willpartially hydrolyze the hemicellulose and cellulose portions of thestover/straw/hulls/biomass fibers. The partial hydrolysis of thecellulosic portion will cause the cellulose to become more susceptibleto degradation by the bacterial cellulases in ruminants. Thermochemicalpretreatment will decrease the crystallinity of the cellulose and renderit more bio-available, and will also degrade the hemicellulose portionsto oligosaccharide fractions. Chemical treatments utilizing acids,bases, or organosolvents can also improve carbohydrate digestibilitythrough the hydrolysis of backbone sugar O-glycosidic linkages, releaseof side chain substituents, separation of hemicellulose from lignin, orsolubilization of hemicellulose and lignin. Enzymatic treatmentsutilizing cellulosic degrading enzymes including but not limited tocellulase and hemicellulase will decrease polymer crystallinity thusimprove bio-availability. The removal of substituents or hydrolysis ofthe polysaccharide backbone chain improves enzymic breakdown of thebiomass fiber by providing increased access to the polymer backbone.Physical pretreatment will decrease the particle size to increasesurface area for more efficient ruminant digestion. The pretreatmentprocess may also increase the hydration capacity (liquid-holdingability) of the lignocellulosic materials. If this is the case, thenenergy-containing materials, preferably in liquid form, such as forexample but not limited to animal fats, vegetable soapstocks, and/orglycerin, and combinations thereof, may be added to the pretreatedlignocellulosic materials of the present invention.

In this manner, the cellulose may replace the starch that is divertedtowards increased fuel ethanol production. Combining this bio-availablecellulose with the DDG/DDGS would provide a sufficient feed for cattle.As is the case with current cattle feed, the new cattle feed would needto be milled and pelletized to provide a high-energy, high-densityanimal feed.

The corn diverted from cattle feed would be processed to ethanol by drymilling, thereby producing the DDG and DDGS as by-products. Dry millingis currently the most cost-effective way to expand the production ofethanol.

This invention also discloses methods to improve the dry millingprocess. As compared to wet milling, dry milling uses less water,generates fewer co-products, and is not as capital intensive. To enhancethe economics of dry milling, new cost-effective ways of processing thecorn prior to fermentation are desirable. The methods of this inventioninclude removing the pericarp and separating the germ prior to grindingand wetting the remaining corn, thus maximizing the amount ofco-products. This invention lowers the viscosity of the fermentationmash and allows for easier conversion of the starch to dextrose byreducing the dry solids. Also, this invention saves energy since thepericarp and germ do not need to be dried. In a further embodiment ofthis invention, the process includes wherein the separated germ andpericarp are further processed for oil and other valuable componentsprior to incorporation into the DDG/DDGS animal feed.

This invention overcomes three of the hurdles currently faced by effortsto convert lignocellulosics such as stover/straw/hulls/other biomassfibers to ethanol. Those hurdles are: first, the recalcitrance ofcellulose to enzymatic degradation due to the lignin seal; second, thehigh amount of energy required to pretreat fibers to enhance theirdigestibility; and third, the economic problems associated with thetransport of low energy density biomass.

The first and second problems are addressed by the bacterial consortiumpresent in the cattle rumen, which produce efficient cellulase complexesand other fibrolytic enzymes for degrading these streams withoutextraneous fermentations. With a minimum pretreatment, and thus aminimum energy input, the digestibility is greatly increased by thecombination of the pretreatment and bacterial rumen enzymes. The thirdproblem is addressed by locating processing plants that will convert theDDG/DDGS and straw/stover/hulls/other biomass fibers to an acceptableanimal feed in areas where the straw/stover/hulls, cattle, and feedmills are presently available or located, thus minimizing expensesassociated with transporting feedstocks with a low energy density. Thesoy hulls may be a feedstock utilized because they are derived fromsoybean processing at soybean crushing facilities and corn germ mealderived from corn wet-milling facilities, therefore are readilyavailable.

This invention provides an improved feed with a variable composition,wherein the exact composition is dependent on which crops are grownnearby. This will depend on the location of the corn dry-mill, thesoybean processing plant, and the plant fiber biomass pretreatmentfacility. Similarly, corn germ meal from the corn wet-milling processmay also be utilized. This process will create new byproduct streamsfrom the modified dry-mill, and will combine those materials withpretreated plant fibers that contain significant quantities ofcarbohydrates. This new feed material will contain a reduced amount ofstarch, and will therefore not be as conducive to rumen acidosis therebyallowing the animal to utilize more of the feed. With an increasedhydration capacity of the plant fibers, energy ingredients, preferablyin a liquid form, such as animal fats, vegetable soapstocks and/orglycerin, and combinations thereof, may be added to the referencedmixing steps in FIG. 5 to develop novel feeds with applications formonogastrics, as well. Also, this invention creates a new dry-millingscheme with novel by-products.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows Step I of the integrated process in which the pericarp isremoved from the corn kernel and optionally processed to removeby-products.

FIG. 2 shows Step II of the integrated process in which the germ isremoved from the corn kernel and optionally processed to removeby-products.

FIG. 3 shows step III of the process in which the protein is removed andfurther milling occurs.

FIG. 4 shows Step IV of the process in which the starch of the cornkernel is saccharified and fermented, and optionally, wherein thefermented beer is distilled to produce ethanol.

FIG. 5 shows Step V of the process in which pretreated lignocellulosicmaterial is mixed with by-products of previous steps of the process toproduce an improved cattle feed.

FIG. 6 shows a schematic representation of a corn kernel showing theconstituent parts thereof.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a method for processing corn kernels comprisingthe steps of removing the pericarp from the corn kernels, removing thegerm from the corn kernels resulting in a starch and a protein,separating the starch and the protein from each other, and saccharifyingand fermenting the starch to produce a fermented starch broth.Preferably, the method of this invention comprises liquefying theseparated starch before the saccharification and fermentation of thestarch. A flow chart of the improved processes of this invention isfound in FIGS. 1-5. The method of the present invention for processingcorn kernels is preferably divided into five general steps: pericarpremoval from the corn kernel; germ removal from the corn kernelresulting in a starch and a protein fraction; separation of the starchand protein; fermentation of the starch to ethanol; and pericarpprocessing and biomass fiber pretreatment. The corn is first processedto remove the pericarp (and likely the tip cap) from the remainingstarch, protein, and germ by a tempering step followed by milling andseparation. The tempering step can include a chemical tempering byutilizing lactic acid at ambient temperatures and pressures, 3% wt/wtgaseous or liquid ammonia addition at ambient temperatures andpressures, or 10% water addition at ambient temperatures and pressures.The milling step could include processing with a Fitz Comminutor Millwith a ¼ inch screen, a Ferrell-Ross Flaking mill with a gap setting of1.1 or a Ferrell-Ross flaking mill with a gap setting of 3. After themilling step, the milled mixture could be aspirated with a 1-inchdifferential on a Kice aspirator to separate the starch granulesfraction and the pericarp fraction from the heavier endosperm and germfraction. Alternatively, the milled fraction could be sieved over acombination of 10 and 40 mesh screens to separate the larger pericarpfraction (larger than 10 mesh) from the endosperm and germ fraction(larger than 40 mesh, smaller than 10 mesh) and from the starch granulesfraction (smaller than 40 mesh). Further milling and separation stepscan lead to further purified corn fractions.

The pericarp is processed to obtain chemicals, food fiber, feed fiber,nutraceutical and possibly pretreated to enhance the digestibility byheating the pericarp to about 150° C. with 1% sulfuric acid for about 30minutes to yield an oligosaccharide containing mixture, extracting thepericarp in a counter-current extractor with ethanol at about 70° C. oralkaline ethanol at about 70° C. to yield a corn fiber oil or a ferulicacid fraction, or hydrolyzing the corn fiber with cellulase,hemicellulase, amylases, and protease enzymes to obtain a fermentablesugar mixture. A combination of the previous treatments could also beutilized, such as heating the pericarp to about 150° C. with 1% sulfuricacid for about 30 minutes followed by adjusting the pH of the mixture toa pH of about pH 5 and adding enzymes as described herein to obtain asugar mixture.

Next, the germ is separated from the starch and protein, and separatelyprocessed to remove oil and sterols. This can occur by processing thecorn endosperm and germ fraction as separated above by further millingthrough a Ferrell-Ross cracking mill with a gap setting of 3 to reducethe endosperm size and then sieve the resulting mixture over a 40 meshscreen to separate the starch fraction (smaller than 40 mesh) from thegerm fraction (larger than 40 mesh). The remaining starch and proteincan be separated and the starch can be extracted to remove the oil andsterols and then fermented. Optionally, the starch and protein may bothbe sent to the ethanol fermentation. The starch and protein fraction canbe liquefied by jet cooking from about 120 to about 150° C. with 0.01%α-amylase at a pressure of about 5.1 bar for about 10 seconds with 2times added weight of water followed by holding the enzyme-starch-cornprotein mixture at about 95° C. for about 10 minutes. Theprotein-liquefied starch stream can then be nanofiltered through afilter with a 1000 molecular weight cutoff to separate the protein fromthe liquefied starch. The starch can be fermented by adding 0.01%glucoamylase and inoculating with Saccharomyces cerevisiae to theliquefied starch fraction at about 30° C. and about a pH of pH 5 forabout 48 hours. The ethanol fermentation broth can be processed toremove the solids by centrifugation and then distilled at temperaturesbetween about 80 and 100° C. to remove the ethanol or it can optionallybe distilled first and then centrifuged. The germ fraction can beprocessed by extraction of the germ with a 7:1 hexane to germ ratio in acounter-current Crown extractor at ambient pressure for about 1 hour atabout 60° C. The germ and hexane are separated over a moving screen, andthe germ can be dried in a desolventizer at about 150° C. at ambientpressure for about 30 minutes to release any remaining hexane. Therecovered hexane can be condensed and reused. The oil-containing hexanecan be processed by methods known in the art to separate, purify andrefine the oil fraction. Finally, the processed germ, pericarp, andother solids are mixed and then blended with, for example but notlimited to, thermochemically pretreated biomass fibers, such as forexample but not limited to, soybean hulls, corn stover, wheat straw, andthe like, or other lignocellulosic materials or crop fibers, before orafter thermochemical treatment to produce a bioavailable modified feed.The thermochemical treatment of the biomass fibers may be hydrolyzed atabout 150° C. for about 30 minutes at a pressure of about 5.1 bar atabout a 30% solids content in a reactor rotating at 1 RPM. Optionally,the pericarp may be processed to obtain chemicals and then pretreated toenhance digestibility for feed, nutraceutical, and food applications. Ifthe pericarp is thermochemically hydrolyzed at about 150° C. for about30 minutes at a pressure of about 5.1 bar at about 30% solids in areactor rotating at 1 RPM, an oligosaccharide containing mixture can beseparated by processing with a Vincent screw-type press. Thisoligosaccharide containing mixture can be heated in an agitated reactor(100 RPM) at about 121 ° C. with 1% added sulfuric acid for about 30minutes at a pressure of about 2.1 bar to produce a monosaccharidecontaining liquid with glucose, xylose, arabinose, galactose, andmannose. This sugar mixture can be fermented to ethanol or otherproducts. If the pericarp is extracted with ethanol at ambient pressureat about 70° C. for about 1 hour, the ethanol extract will containphytosterols, free fatty acids, and triglycerides.

Referring to FIG. 1 in which Step I of the process is shown, in box 10,pericarp 120 is removed from, for example but not limited to, cornkernels 100. One possible method of separating pericarp 120 is by alkalidebranning, such as for example, by adding a 1% sodium hydroxidesolution in a 7:1 alkali solution to corn kernels mixture at ambientpressure and about 60° C. for about 10 minutes. Alternately, a 3%aqueous ammonia solution can be added at about 60° C. for about 10minutes at ambient pressure with agitation at a 7:1 ratio of ammoniasolution to corn kernels. This method, for example but not limited to,may be accomplished with a hot caustic soda solution or aqueous ammoniasolution, which would hydrolyze the chemical bonds between pericarp 120and endosperm 140 (see FIG. 6—corn kernel example components) so thatmechanical equipment as detailed herein can separate the components.Acid debranning with mineral or organic acids is able to penetrate intokernel 100 and break the bonds between pericarp 120 and endosperm 140.This could be accomplished with 1% sulfuric, acetic, or lactic acid in a7:1 ratio of acid solution to corn kernels at about 60° C. for about 10minutes at ambient pressure. Finally, another example of the method ofthe this invention includes first conditioning of kernel 100 with steamor hot (having a temperature of from about 50° C. to about 99° C.) water(tempering) at about a 10% wt mixture of water to corn kernels at about60° C. for about 1 hour, followed by milling as detailed herein toabrade pericarp 120 from the remainder of corn kernel 100. All of theprevious methods need to be followed by a physical separation step,which will use a mill, as detailed herein. The mills that may be used,such as for example but not limited to, include a disc mill, a crackingroll mill, a flaking mill, a Fitz comminutor mill, or a Boston shearpump. The milling step may be followed by an additional separation step,which may utilize a vacuum suction separator, a cyclone, a hydroclone, asieve with 10 and 40 mesh sizes, or an aspirator. The corn kernelfractions without the pericarp 120 are the result of Step I of theprocess of this invention.

The separated fractions of the corn will be processed for furtherby-products. The removed pericarp 120 can be solvent extracted to removeby-products 104, such as phytosterols, if they are present, and/ortreated with aqueous acid or base or with a acidic or basic solvent, allof which solvents are known in the art, at about 70° C. for about 1 hourat ambient pressure in a Crown counter-current extractor for theextraction of the hemicellulose, either oligosaccharides or the intacthemicellulose, other lignins, and other lignin precursors, or to releaseferulic acid or coumaric acid from the hemicellulose chains. Thesecomponents could be separated by ion exchange chromatography from theremaining liquid, or other lignin precursors. This can be done bytreating the pericarp with alkali, ethanolic alkali, acid or ethanolicacid, depending on the component of interest. By-products 106 comprisedmainly of fiber, are used later in the integrated process as a componentof the final cattle feed product.

Referring now to FIG. 2 showing Step II of the process, followingremoval of pericarp 120, germ 125 will be removed from endosperm 140 inbox 12, as detailed above. For example but not limited to, a method thatmay be used to separate the components is lactic acid steeping, whichallows for the hydrolysis of chemical bonds between endosperm 140 andgerm 125 (FIG. 6). This could be accomplished by adding a 1% lactic acidsolution at a 2:1 ratio of solution to germ and endosperm mixture atabout 70° C. for about 1 hour. Enzyme hydrolysis for the separation ofendosperm 140 and germ 125 can also be used wherein 0.01 wt % hightemperature (80° C. to 99° C.) α-amylase is added to about a 30% drysolids germ-endosperm mixture, and the mixture heated from about 120 toabout −150° C. for about 10 seconds to liquefy the starch. The germfraction could then be removed by passing the solution through a screento separated out the germ pieces. Again, the methods described may needto be followed by a physical separation step using a mill or sieve. Themills that may be used include, for example but not limited to, a discmill, a cracking roll mill, a flaking mill, and a Boston shear pump. Themilling may also be followed by a separation step utilizing a vacuumsuction separator, a cyclone, a hydroclone, or an aspirator. The removalof germ 125 leaves a starch slurry, fine fiber and protein withoptionally an aleurone layer. The output of Step II of the process is astarch slurry, fine fiber and protein, and optionally an aleurone layer108.

Germ 125 can be processed, in box 42 could be further processed forextraction of oil and other nutraceuticals 130, by practices know in theart, such as by hexane, heptane, ethanol, other organic solvents,sub-critical water extractions, supercritical CO₂, etc. Generally, thegerm is extracted as detailed above at about 60° C. with a 7:1 ratio ofhexane to germ in a Crown counter-current extractor for about 1 hour atambient pressure. The processed germ results in oil 130 containingtriglycerides and tocopherols and germ by-product 132, comprisedprimarily of fiber, which may also be used later in the integratedprocess as a component of the improved cattle feed.

In FIG. 3, showing Step III of the process, protein 110 will beseparated from the starch slurry, fine fiber and protein mixture 108. Inbox 16 further milling may be required to reduce starch 112 to starchgranules, and in box 18, protein 110 is extracted, leaving starch 112and fine fiber. Starch 112 and protein 110 can be separated by clamshelland centrifuge processing if they are in a slurry, or by solubilizationof starch 112 by enzyme saccharification or jet cooking as detailedabove. Another method of separating the protein and starch is thesolubilization of the starch by enzyme saccharification, starch 112 willbe hydrolyzed to oligosaccharides or, in the case of jet cooking, starch112 will be gelatinized and solubilized. Starch 112 and protein 110 canalso be separated by membrane filtration. This step results in starch112 and fine fiber

FIG. 4 shows Step IV of the process. In box 20, the starch portion ofstarch and fine fiber 112 will be saccharified and fermented as setforth herein. Optionally, in box 22, the solids, comprising the fibercomponents and fermentation solids 135, are separated, and, in box 24,the fermentation broth 137 is distilled to ethanol 115, wherein thedistilled ethanol has a proof ranging from about 180 to about 190 proof,or from about 90% to about 95%. Alternatively, in box 20, thefermentation broth containing the liquids and solids can be distilledfirst, as in box 24, and then the stillage 117, containing thefermentation solids and fine fiber, 135, can be separated from theethanol and then further separated from the remaining liquid. This stepmay be accomplished using advanced fermentation techniques to improvethe yield and efficiency of the fermentation. Stillage 117 is aby-product of the distillation process. This can be evaporated to form aconcentrate, which is added to the fermentation solids and fine fiber.This mixture may be dried to produce a modified Distillers Dried Grains(DDG) or Distillers Dried Grains with Solubles (DDGS) for animal feed.

In Step V of the process of the present invention, shown in FIG. 5,biomass fibers obtained from plants, such as various lignocellulosicmaterials, such as corn stover, wheat straw and soybean hulls 125 formthe basis of the improved modified animal feed of the invention. In apreferred embodiment of the invention, these biomass fiber materials canbe pretreated, in box 26, by aqueous acid, base, or mechanical methods,to increase the digestibility of those materials. The biomass fibermaterials can be treated by adding 5 wt % calcium hydroxide to thebiomass fiber samples and then heating at about 150° C., at a pressureof about 5.1 bars for about 30 minutes with direct steam injection in arotating reactor, rotating at 1 RPM. Alternately, the biomass fibermaterials can be treated by adding 3 wt % ammonia to the biomass fibersample and treated as above. Alternatively, the biomass fiber samplescan be treated with 1% sulfuric acid and treated as above.Alternatively, the biomass fiber materials can be processed through amechanical macerator or extruder to reduce the particle size.Alternatively, the biomass fiber materials can be process through amechanical macerator or extruder with any of the above chemicals added.Preferably, the pretreatment can be accomplished by mixing the biomassfibers with stillage at about 80° C. 117 from the distillation of thefermentation broth from box 24 in Step IV, and heating the mixturefurther to about 150° C. with the optional addition of other chemicals,such as enzymes, known by those skilled in the art to further enhancedigestibility of the material for cattle as set forth herein. Themixture can be heated for about 30 minutes at a pressure of about 5.1bar in a rotating reactor, rotating at 1 RPM. Other physical andthermochemical methods, know by those skilled in the art, may beemployed to increase the digestibility of the lignocellulosic materialsor the materials remaining after the corn milling process of thisinvention. The hydration capacity (liquid holding capability) of thebiomass fibers, such as the lignocellulosic materials(hulls/straw/stover/other biomass fibers) may also be increased by thisprocess, so energy-containing materials, preferably in a liquid form,such as animals fats, vegetable soapstocks, and/or glycerin, andcombinations thereof, may be added to increase the caloric content ofthe modified animal feed of the present invention.

In box 28 the pretreated lignocellulosic materials 125, previously mixedwith the stillage 112, are mixed with energy containing materials,preferably in a liquid form (for example, animal/vegetable fats,glycerin, and soapstocks, etc.), fermentation solids and fine fiber 135(DDG/DDGS) and then agglomerated (pelleted or extruded) to form thebasic animal, such as for example cattle, feed product of thisinvention. Germ by-products 132 and pericarp by-products 106 mayoptionally be mixed in, at box 30, to make up another embodiment of thebioavailable modified animal feed 130 of the present invention.

In another embodiment of this invention, the by-products from Steps Iand II, the processed pericarp 120 and germ 125 respectively, and anyother solids from the corn milling process can also be optionallypretreated as described herein (this step not shown in figures).

Those persons skilled in the art shall appreciate that various methodsmay be used to pretreat the biomass fibers, including alkalinetreatments, acid treatments, heat treatments, mechanical treatments, andenzyme treatments on many different types of lignocellulosic materials,including soybean hulls, soybean straw, wheat straw, wheat hulls, wheatmidds, wheat C starch, corn fiber hulls, corn gluten feed, corn stover,corn cobs, corn germ meal, barley mill waste, oat hulls, oat straw,cottonseed, cotton gin waste, rice hulls, rice straw, sugar canebagasse, sugar beet pulp, orchard grass, fescue, switchgrass, alfalfa,other forage crop fibers, etc. as set forth herein. The alkalinetreatments may include, but are not limited to, treating thelignocellulosic materials with liquid caustic or liquid caustic andperoxide to help degrade the fibrous plant biomass, or with gaseousammonia. The acid treatments include dilute acid addition to the biomassand optional heating to reduce the crystallinity of the cellulose and tobreak down the polysaccharides to oligosaccharides. Thephysical/mechanical treatment can optionally use steam explosion and/ormechanical size reduction to increase the surface area for attack byrumen microbial flora enzymes, and also to reduce the crystallinity ofthe cellulose, which will increase the digestibility of the cellulose.Finally, the enzyme treatment will be used to degrade the biomass tooligosaccharides. Those persons skilled in the art shall appreciate thatthese treatments can be used in various combinations.

Corn kernels 100 may also be optionally pretreated by treatment withvarious chemicals, alkalis, acids and enzymes, after which the corn willbe milled to first remove pericarp 120 and then to remove germ 125. Theequipment used for milling and separating includes for example but notlimited to cracking roll mill, flaking mill, aspirator, conditioner, anda Boston shear pump. After pericarp 120 and germ 125 have beenseparated, the remaining starch/protein mixture can be processed toseparate the starch from the protein, or could be heat treated withsteam and enzymes to convert the starch to oligosaccharides. After thefermentation of the glucose to ethanol, the solids, mainly yeast, in thefermentation media will be separated by using a solid bowl centrifuge.The yeast can be recycled to the fermentor vessel or used in otherapplications to produce food or feed flavors. The yeast or portions ofthe processed yeast may also be mixed into the animal feed product, 130.The ethanol-containing fermentation broth will then be distilled, andthe remaining stillage at about 80° C. will preferably be used as awater source for the thermochemical hydrolysis of the biomass fibers.The biomass fibers will then be mixed with the solids from thedry-milling process to create an enhanced animal feed.

To market the bioavailable modified animal feed of the present inventioncomprising the pericarp removed from corn kernels, germ removed fromcorn kernels, and pretreated biomass fibers transportation,pretreatment, milling, and mixing issues have been considered.Currently, corn stover is left on the fields, while wheat straw iseither baled or left on the fields. The soy hulls, oat hulls, or corngerm meal and DDG/DDGS would be easily collected from the processingplants where they are produced; however, due to their low bulk density,the transportation costs for crop residues from the field to thethermochemical processing plant would be high unless these facilitiesare located within reasonable distances.

The transportation of the corn stover and wheat straw could be addressedby collection from the field and transportation to a central locationwithin, for example but not limited to, a 30 mile radius. At that site,the thermochemical treatment could take place and the pretreated slurryor pretreated solids could be transported to the local feed mill whereit could be mixed with the DDG/DDGS. The soy hulls, oat hulls, or corngerm meal could be treated similarly by pretreating the hulls or meal atthe plant where they are produced. The pretreated biomass would have ahigher bulk density, thereby decreasing the overall transportationcosts.

The issues associated with the distribution of the DDG/DDGS could bereduced by building small dry mills distributed over a large area wherecorn is produced. This would decrease the distance that the cornfeedstock would need to be transported as well as decreasing thedistance that the DDG/DDGS would need to be transported. The localthermochemical pretreatment sites would also need to be distributedwhere the corn stover and wheat straw feedstocks are produced todecrease the distances of transportation.

The process of this invention represents an improvement over thebackground art dry-grind process for ethanol, in which the entire cornkernel is milled and processed, including the entire pericarp 120 andgerm 125, which are carried through the fermentor. Removing some of thenon-fermentables before fermentation, especially when combined withadvanced fermentation technology, can increase the efficiency offermentation and co-product dewatering. This will not only save money byusing less energy for drying the co-products, but the co-products can beprocessed to obtain additional products. In the case of germ 125, theco-products removed by processing may be corn oil and tocopherols, andfor pericarp 120, phytosterols may be extracted, depending with whichfraction the aleurone layer remains. The value of these co-products alsolowers the overall cost of ethanol production.

In the background art corn wet-milling process, corn is steeped withwater and SO₂ for up to 48 hours. During the steeping, lacticacid-producing bacteria ferment a portion of the corn solubles. Thisprocess softens the kernel by allowing SO₂ and lactic acid to enter thecorn kernel through the tip cap, which allows separation of the variousparts of the corn by milling and density differences. The SO₂ and lacticacid hydrolyze the chemical bonds between the various components of thecorn kernel and also help to break down the starch-protein matrix in theendosperm, allowing for efficient separation of the starch. As discussedabove, the known in the art dry milling process simply grinds the entirekernel without separation of the components. The methods of the presentinvention include a process wherein the corn kernel is separated intoits components without the use of large volumes of water and longsteeping times employed in the background art, and, therefore representan improvement over known art processes.

The process of this invention as described herein allows the diversionof the starch portion of the corn kernel for production of ethanol. Theportions of the corn kernel not used in the production of ethanol areutilized as a component of the modified animal feed of this inventionand which are supplemented with pretreated plant derived biomass fibers,such as for example but not limited to, soybean hulls, wheat straw andcorn stover, to replace the starches diverted to ethanol production. Thenew animal feed of this invention contains a reduced amount of starch (astarch content of from about 5 to about 15 weight %) and will thereforenot be as conducive to rumen acidosis thereby allowing the animal toutilize more of the animal feed of this invention. The hydrationcapacity of the treated biomass fibers of the animal feed of the presentinvention will allow for the addition of energy sources (e.g., DDG/DDGSand energy materials as described herein, preferably in the form ofliquids) so that monogastrics have feed stuffs to replace a portion ofthe starch from corn.

EXAMPLES Example 1 Dry Corn Fractionation

Corn milling tests have been conducted on dry fractionation of cornkernels at ADM. This run consisted of placing 5 kg of corn kernels in arotating sealed vessel and adding 10% water. The vessel was rotated for1 hour and then the kernels were removed. The tempered corn kernels wereroughly ground through a ¼″ Fitz Comminutor; followed by aspirationthrough a Kice aspirator with a 1″ differential; the “overs” and“throughs” from the aspirator were sieved at 6, 12, and 20 mesh sizes.After sieving, the large particles from the “throughs” were rollermilled twice at a gap setting of 1.1 on the Ferrell-Ross Flaking milland then sieved at 6 and 12 mesh sizes. The fines (20 mesh or below)were combined prior to analysis. This produced 6 fractions as shown inTable 2 below.

The results show that the Fines are highly enriched in starch ascompared to the native kernels, as well as enriched in NDF (neutraldetergent fiber, equivalent to hemicellulose, cellulose and lignin) anddepleted of fat and protein. This fines fraction is the largest fractionat 35.6%. Other samples enriched in starch include the Grits (33.6% ofthe yield) and Rolled Fines (10.1% of the yield). These fractions arealso enriched in NDF and protein. The grits fraction is compositionallysimilar to the overall corn kernel composition.

TABLE 2 10% Moisture Tempered Corn—Fractions Compositions (%) YieldProtein Ash Fat NDF* Starch Corn Kernels 7.42 3.94 1.51 71.38 Fines35.60 6.16 0.60 2.18 2.90 87.15 Grits 33.60 9.39 1.10 4.21 5.06 76.95Rolled Fines 10.10 7.97 0.64 2.74 3.45 83.85 Germ 2.70 16.50 6.29 19.4717.45 33.59 Pericarp 10.00 8.78 1.68 3.97 43.30 36.57 Rolled Pieces 8.0012.10 2.97 8.54 9.02 64.07

Example 2 Treatment of Biomass Fibers

Several biomass fibers have been obtained and have been prepared forexperimentation. Wheat straw, rice hulls, rice straw, corn stover andoat hulls were ground in a Fitz Mill Comminutor (Chicago, Ill.) to auniform size through a ½″ screen. Distiller's dried grains withsolubles, corn gluten feed (CGF), and soy hulls were also tested, butnot ground.

The ground biomass fibers were treated with thermochemical treatments toincrease biomass digestibility. Two treatments have been conducted, thefirst treatment with 10 w/w % calcium hydroxide and the second treatmentwith 2 w/w % ammonium hydroxide.

In the treatments with 10% calcium hydroxide, I kg (as-is basis) of eachof the ½″ ground biomass fibers were mixed with 100 grams of calciumhydroxide in a tumbler reactor and heated with direct steam injection to145° C. for 30 minutes. The biomass fiber mixtures were removed from thereactor and the masses were recorded.

In the treatment with 2% ammonium hydroxide, 1 kg (as-is basis) of eachof the ½″ ground biomass fibers were mixed with 100 mL of 20% ammoniumhydroxide in a tumbler reactor and heated with direct steam injection to145° C. for 30 minutes. The biomass fiber mixtures were removed from thereactor and the masses were recorded. Table 3 details the amount offiber solubilized by the treatment.

The treated biomass fiber samples were sent to the ADM AllianceNutrition Research Center in Decatur, Ind. for analysis anddetermination of digestibility in cattle rumen. Samples were analyzedfor 24-hour in situ dry matter (DM) and neutral detergent fiber (NDF)disappearance as well as typical chemical constituents (crude protein(CP), NDF, acid detergent fiber (ADF), acid detergent insoluble nitrogen(ADIN), neutral detergent insoluble nitrogen (NDIN), and ash). Sampleswere fermented in duplicate using a minimum of two animals and analysisof DM and NDF obtained for individual in situ bags as replication. Table4 lists the composition of the fibers before and after pretreatment, andTable 5 details the change in digestibility of the fibers pre- andpost-treatment.

The efficacy of CaOH and ammoniation was affected by sample type, butCaOH treatment was generally more effective than ammoniation under theseprocessing conditions. When adjusted for initial ingredient values,increased fermentability of fiber was correlated with the decrease inhemicellulose due to treatment. This would be expected from basetreatments and titration of ester bonds. Initial calculations ofhemicellulose were negative for rice hulls, which is likely due torecovery of biogenic silica in the ADF procedure. Ash values were quitehigh for the rice hull samples and NDF was poorly digested regardless oftreatment. Unexpectedly, ammoniation increased NDF content of the grainby-products. NDF insoluble nitrogen was also increased for thesesamples, suggesting increasing association of protein with fiber in thistreatment. Dry matter and NDF digestion were improved with CaOHtreatment for all treatments, although the effect on wheat straw wasminimal. The effect of ammoniation on fiber digestion was variable withsmall improvements for several ingredients, decreased NDF digestion forrice hulls and corn stover, and substantial improvements for rice andwheat straws (numerically greater than CaOH). The rumen undigestedprotein (RUP) of treated samples was elevated for both chemicaltreatments, reflecting the effects of heat on rumen digestibility ofprotein.

These results suggest that CaOH treatment is more robust thanammoniation. Ammoniation can be considered for select ingredients butdoes not appear broadly applicable. Decreases in hemicellulose can beconsidered as a screening tool to rank treatment conditions.

TABLE 3 Solubilization Results for Biomass Fiber Experiments AmmoniaTreatment Calcium Hydroxide Treatment % Added Dry Added Dry Dry BiomassMass Solids in Dry solids % Mass Solids in Solids % Dry Solids (kg)Liquid, % Mass Solubilized (kg) Liquid, % Mass Solubilized Corn 88.1 5.52.08 114.4 13.0% 5.665 3 169.95 19.3% Stover Wheat 89.4 5.17 1.75 90.510.1% 4.9 3.39 166.11 18.6% Straw Oat 86.65 5.13 1.25 64.1 7.4% 5.5953.15 176.24 20.3% Hulls Soy 93 5.26 4.41 232.0 24.9% 5.26 5.25 276.1529.7% Hulls Rice 90.95 5.75 2.4 138.0 15.2% 3.87 4.95 191.57 21.1% StrawRice 91.18 4.88 1.5 73.2 8.0% 5.74 2.09 119.97 13.2% Hulls DDGS 91.657.07 5.45 385.3 42.0% 5.42 8.35 452.57 49.4% CGF 89.35 6.17 6 370.241.4% 5.205 7.4 385.17 43.1%

TABLE 4 Effect of Ammoniation or Ca Hydroxide Processing on SampleChemistry Ingredient Native CaOH NH₃ Average Native CaOH NH₃ Average NDFADF CGF 30.1 22.4 44.0 32.2 11.7 19.3 21.3 17.4 Corn Stover 75.7 60.769.0 68.5 50.3 55.1 49.6 51.7 DDGS 33.2 26.7 47.3 35.7 20.8 21.9 28.323.7 Oat Hulls 76.5 57.9 83.9 72.8 45.1 49.2 53.3 49.2 Rice Hulls 66.160.9 71.5 61.2 66.3 65.4 72.5 68.1 Rice 62.0 64.1 55.4 60.5 52.2 56.646.7 51.8 Straw Soy Hulls 64.5 64.3 72.8 67.2 48.8 59.9 64.6 57.8 Wheat68.7 72.3 61.0 67.3 53.0 54.3 52.8 53.4 Straw Average 61.1 54.7 64.444.1 48.2 49.5 HemiCellulose¹ ADI-CP CGF 18.4 3.1 22.7 14.7 1.6 5.4 4.94.0 Corn Stover 25.4 5.6 19.4 16.8 0.8 1.2 2.3 1.4 DDGS 12.4 4.8 19.012.1 6.2 7.9 12.3 8.8 Oat Hulls 31.4 8.7 30.6 23.6 0.3 0.8 0.8 0.6 RiceHulls −0.2 −4.5 −1.0 −1.9 0.8 1.1 1.2 1.0 Rice Straw 9.8 7.5 8.7 8.7 0.71.8 1.2 1.2 Soy Hulls 15.7 4.4 8.2 9.4 1.3 3.9 3.6 2.9 Wheat Straw 15.718.0 8.2 14.0 0.8 2.1 1.6 1.5 Average 17.0 6.4 15.0 1.5 2.9 3.3 NDI-CPAsh CGF 4.3 7.3 6.5 6.0 7.4 21.2 8.4 12.3 Corn Stover 1.4 1.1 2.4 1.63.9 11.2 6.6 7.2 DDGS 4.9 10.3 16.6 10.6 4.2 16.9 4.0 8.4 Oat Hulls 0.80.9 1.1 0.9 5.8 11.3 5.9 7.7 Rice Hulls 0.9 1.3 1.5 1.2 17.3 21.6 18.119.0 Rice Straw 0.9 2.1 1.6 1.5 15.2 17.3 22.5 18.3 Soy Hulls 3.2 3.84.3 3.8 4.0 10.9 4.0 6.3 Wheat Straw 1.4 2.2 1.3 1.6 7.7 6.3 14.5 9.5Average 2.1 3.4 4.1 7.8 14.0 9.9 ¹Hemicellulose = NDF-ADF

TABLE 5 Effect of Ammoniation or Ca Hydroxide Processing on RumenDigestion of DM, NDF and CP Dry Matter Digestion (i) TreatmentsImprovement (x) Native CaOH NH₃ Ing. Ave. CaOH NH₃ CGF 78.6 93.1 80.984.2 1.18 1.03 Corn Stover 28.5 56.8 28.9 38.0 1.99 1.01 DDGS 63.5 85.573.9 74.3 1.35 1.16 Oat Hulls 24.6 52.9 20.9 32.8 2.15 0.85 Rice Hulls13.2 26.2 9.2 16.2 1.99 0.70 Rice Straw 29.6 44.6 62.4 45.5 1.51 2.11Soy Hulls 61.6 69.4 43.3 58.1 1.13 0.70 Wheat Straw 29.5 29.8 50.7 36.71.01 1.72 Average 39.3 56.5 44.0 1.5 1.2 SEM = 2.4, SEM of ingredientaverages = 2.0, SEM of treatment averages = 1.8 NDF Digestion (ii)Treatments Improvement (x) Native CaOH NH₃ Ave CaOH NH₃ CGF 48.6 84.166.5 66.4 1.73 1.37 Corn Stover 22.9 44.0 13.8 26.9 1.93 0.61 DDGS 42.177.3 66.6 62.0 1.84 1.58 Oat Hulls 15.4 37.6 18.3 23.8 2.45 1.19 RiceHulls 5.1 11.8 2.2 6.4 2.30 0.43 Rice Straw 15.5 35.1 47.7 32.8 2.273.08 Soy Hulls 51.5 58.4 34.3 48.1 1.13 0.67 Wheat Straw 17.2 18.3 35.223.6 1.06 2.04 Average 26.1 44.8 33.5 1.8 1.4 SEM = 3.2, SEM ofingredient averages = 2.5, SEM of treatment averages = 2.3 RUP (iii)Treatments Improvement (x) Native CaOH NH₃ Ave CaOH NH₃ CGF 87.0 — 93.3— — 1.07 Corn Stover 18.2 58.2 66.6 47.7 3.19 3.65 DDGS 48.6 76.9 73.666.4 1.58 1.51 Oat Hulls 42.9 69.2 51.0 54.3 1.61 1.19 Rice Hulls 38.929.1 36.9 35.0 0.75 0.95 Rice Straw 11.2 71.2 67.0 49.8 6.37 5.99 SoyHulls 72.7 74.5 68.2 71.8 1.02 0.94 Wheat Straw 16.4 53.9 56.6 42.3 3.293.45 Average 42.0 61.9 64.2 2.5 2.3 SEM = 4.1, SEM of ingredientaverages = 3.3, SEM of treatment averages = 2.9

Example 3 Readco Processing of Wheat Straw and Corn Stover

The Readco processor is a double shaft mixer, which exerts mechanicalshear on the material processed, leading also to increased temperatures.It could be an ideal processing device for impregnation of ammonia orother chemicals. Several treatments to increase the digestibility of thebiomass samples were planned and they are shown in Table 6. The amountof chemical added could be less if the treatment distributes thechemical more effectively.

TABLE 6 Readco processing of wheat straw and corn stover Trt. #Treatment Amount added as a % of DM Total Moisture 1 Anhydrous NH₃ 3 352 Anhydrous NH₃ 6 35 3 CaO 2.5 35 4 CaO 5 35 5 CaO 10 35 6 NaOH and H₂O₂5 and 3 50 7 NaOH and H₂O₂ 2.5 and 1.5 50 8 NaClO 200 ppm 30 9 NaClO 100ppm 30

Those skilled in the art shall appreciate that the present inventionprovides a method of processing corn kernels to obtain a high proof(from about 180 to about 190 proof) ethanol and a modified animal feed.

The methods and processes illustratively described herein may besuitably practiced in differing orders of steps. They are notnecessarily restricted to the orders of steps indicated herein or in theclaims.

As used herein and in the appended claims, the singular forms “a,” “an,”and “the” include plural reference unless the context clearly dictatesotherwise.

Under no circumstances may the patent be interpreted to be limited tothe specific examples or aspects or methods specifically disclosedherein. Under no circumstances may the patent be interpreted to belimited by any statement made by any Examiner or any other official oremployee of the Patent and Trademark Office unless such statement wasspecifically and without qualification or reservation expressly adoptedby Applicants in a responsive writing specifically relating to theapplication that led to this patent prior to its issuance.

The terms and expressions employed herein have been used as terms ofdescription and not of limitation, and there is no intention in the useof such terms and expressions, or any portions thereof, to exclude anyequivalents now known or later developed, whether or not suchequivalents are set forth or shown or described herein or whether or notsuch equivalents are viewed as predictable, but it is recognized thatvarious modifications are within the scope of the invention claimed,whether or not those claims issued with or without alteration oramendment for any reason. Thus, it shall be understood that, althoughthe present invention has been specifically disclosed by preferredembodiments and optional features, modifications and variations of theinventions embodied therein or herein disclosed can be resorted to bythose skilled in the art, and such modifications and variations areconsidered to be within the scope of the inventions disclosed andclaimed herein.

Specific methods and compositions described herein are representative ofpreferred embodiments and are exemplary and not intended as limitationson the scope of the invention. Other objects, aspects, and embodimentswill occur to those skilled in the art upon consideration of thisspecification, and are encompassed within the spirit of the invention asdefined by the scope of the claims. Where examples are given, thedescription shall be construed to include but not to be limited to onlyto those examples. It will be readily apparent to one skilled in the artthat varying substitutions and modifications may be made to theinvention disclosed herein without departing from the scope and spiritof the invention, and from the description of the inventions, includingthose illustratively set forth herein, it is manifest that variousmodifications and equivalents can be used to implement the concepts ofthe present invention without departing from its scope. A person ofordinary skill in the art will recognize that changes can be made inform and detail without departing from the spirit and the scope of theinvention. The described embodiments are to be considered in allrespects as illustrative and not restrictive. Thus, for example,additional embodiments are within the scope of the invention and withinthe following claims.

1. A method for processing corn kernels comprising the steps of:removing the pericarp from said corn kernels to obtain a pericarpenriched fraction; contacting at least one of the pericarp enrichedfraction and a lignocellulosic by-product of agricultural processingwith a fiber hydrolyzing agent to at least partially hydrolyzelignocellulosic fibers and obtain a treated fiber fraction; removing thegerm from said corn kernels, resulting in a starch and a protein;separating said protein from said starch; liquefying and saccharifyingand fermenting said starch to produce a fermented starch broth;recovering ethanol and distillers dried grains from the fermented starchbroth; and combining the treated fiber fraction with the distillersdried grains to form a modified distiller's dried grain product.
 2. Themethod of claim 1 including liquefying said separated starch before saidsaccharification and fermentation of said starch.
 3. The method of claim1 including wherein said step of removing said pericarp comprises thesteps of: chemically separating said pericarp from the remainder of saidcorn kernel by alkali debranning, acid debranning, or gaseous or liquidammonia addition of said corn kernel; and milling said separatedpericarp.
 4. The method of claim 1 including wherein said step ofremoving said pericarp comprises the steps of: conditioning said cornkernels with steam or hot water having a temperature from about 50° C.to about 99° C.; and milling said corn kernels to abrade and remove saidpericarp.
 5. The method of claim 1 including wherein step of removingsaid germ from said corn kernels comprises the steps of: utilizing alactic acid steeping to hydrolyze the chemical bonds between theendosperm and said germ or utilizing enzyme hydrolysis to separate saidgerm from the endosperm; and milling said corn kernel to remove saidgerm.
 6. The method of claim 1 comprising the steps of: processing saidstarch and protein to remove oils and sterols therefrom; and millingsaid starch to granularize said starch.
 7. The method of claim 1including wherein said step of separating said starch and protein isaccomplished utilizing a method selected from a group consisting of clamshell processing, centrifuge processing, solubilization of said starchportion by enzyme saccharification, jet cooking and membrane filtration.8. The method of claim 1 wherein obtaining the treated fiber fractioncomprises contacting the pericarp enriched fraction with the fiberhydrolyzing agent.
 9. The method of claim 8 wherein obtaining thetreated fiber containing fraction further comprises contacting thelignocellulosic by-product of agricultural processing with the fiberhydrolyzing agent.
 10. The method of claim 8 comprising the step ofprocessing said pericarp enriched fraction to obtain pericarpby-products prior to contacting the pericarp enriched fraction wit thehydrolyzing agent.
 11. The method of claim 10 including wherein saidby-products of said pericarp processing include phytosterols,hemicelluloses, ferulic acid, and coumaric acid.
 12. The method of claim1 wherein obtaining the treated fiber fraction comprises contacting thelignocellulosic by-product of agricultural processing with the fiberhydrolyzing agent.
 13. The method of claim 1 wherein the fiberhydrolyzing agent comprises at least one composition selected from thegroup consisting of calcium hydoxide, calcium oxide, sodium hydroxide,hydrogen peroxide, ammonia and a hypochlorite salt.
 14. The method ofclaim 1 wherein the lignocellulosic by-product of agriculturalprocessing comprises at least one member selected from the groupconsisting of corn gluten fiber, corn stover, distillers dried grains,oat hulls, rice hulls, rice hulls, rice straw, soy hulls, and wheatstraw.